in reply to How might one determine empty XML payload?

Hi vlturner,

Here's one way:

my $xml = q{<?xml version="1.0" encoding="UTF-8"?><response></response
+>};
my $dom = XML::LibXML->load_xml(string=>$xml);
my $isEmpty = !$dom->documentElement->nonBlankChildNodes;
print "isEmpty: ", ($isEmpty?"yes":"no"), "\n";
__END__
isEmpty: yes

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This method has the advantage that whitespace inside the <response> tag is ignored. If you don't want that, and want to know specifically when the <response> tag has no content at all, use hasChildNodes instead of nonBlankChildNodes.

Hope this helps,
-- Hauke D

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Re^2: How might one determine empty XML payload?
by vlturner (Sexton) on Jun 02, 2016 at 14:11 UTC

    I'm a bit confused here. $input_xml should change to the value you set in $xml when my database request gets to the end of the table. So I substituted $xml for $input_xml and I am getting the following error. Not sure how to use the library correctly yet.

    XML::LibXML->load: specify location, string, or IO at ./ServiceNowCMDB_ALL_CI_DumpXML.pl line 99.

[reply]

      Hi vlturner,

      XML::LibXML->load: specify location, string, or IO at ...

      What does the code look like that is causing this error? Maybe $input_xml is undef (Data::Dumper), or perhaps you wrote XML::LibXML->load_xml($input_xml) by accident?

      Regards,
      -- Hauke D

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[d/l]
[select]

        Here is the code.

        my $input_xml;

open my $fh, '>>:encoding(utf8)', $outputfile or die "Cannot open: $ou
+tputfile: $!";

do {
        my $dom = XML::LibXML->load_xml(string=>$input_xml);
        my $isEmpty = !$dom->documentElement->hasChildNodes;
        print "isEmpty: ", ($isEmpty?"yes":"no"), "\n";
        say $fh $input_xml;
        $offset = $offset + $record_limit +50000 ;
        print "Offset=$offset\n";
} while ($input_xml = Get_CMDB_CI());
close($fh) || warn "close failed: $!";

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